Binocular image display apparatus

Abstract: This invention relates to a multi-eye image display apparatus. The apparatus has right-eye moving image display means (4R) for emitting light to display a moving image for the right eye, right-eye still image display means (5R) for emitting light to display a still image for the right eye, left-eye moving image display means (4L) for emitting light to display a moving image for the left eye, left-eye still image display means (5L) for emitting light to display a still image for the left eye and optical means (2R,2L) for guiding a light beam from the right-eye moving image display means (4R) and a light beam from the right-eye still image display means (5R) to the pupil of the right eye (1R) of an observer and guiding a light beam from the left-eye moving image display means (4L) and a light beam from the left-eye still image display means (5L) to the pupil of the left eye (1L) of the observer, whereby the observer can make fusion between the still images and fusion between the moving images.

Description: The present invention relates to a binocular image display apparatus with an optical system for guiding light from images displayed on compact display devices (for example liquid crystal display devices, or CRTs) to form enlarged virtual images thereof in front of an observer so that the observer can observe the virtual images as one single image. Large CRT display apparatus, projection TVs, etc. have been used conventionally as apparatus for displaying a large-screen image from an image displayed on an image display device such as a liquid crystal. These apparatus, however, had problems of various restrictions on operating circumstances; for example, they have needed a large space, it has been hard to observe a good image without dark surroundings, etc. Because of these problems, various binocular image display apparatus have been proposed recently in such an arrangement that light is projected from images displayed on image display devices directly to the eyes (the observer's pupils) through an optical system disposed very close to the face so as to permit the observer to observe large-screen image information, a stereoscopic image, or a panorama image. Among binocular image display apparatus, a goggle-type head mounted display (hereinafter referred to as "HMD") to be mounted on the head is relatively easy of observation of virtual large-screen images as enlarged from images displayed on compact liquid crystal displays (hereinafter referred to as "LCD") by optical systems such as lenses. Stereoscopic binocular HMDs are described, for example, in EP-A-0539907 and GB-A-2206421. An object of the present invention is to provide a binocular image display apparatus suitable for HMD or the like which properly displays still images for the both eyes around moving images for the both eyes whereby an observer can observe moving images displayed as enlarged virtual images ahead of the observer without feeling tired. More particularly, an object of the present invention is to provide a binocular image display apparatus which can facilitate perception of the positions and sizes of virtual images and which can facilitate the fusion of left and right images by such an arrangement that still images are provided around moving images formed by moving image displaying means and that at least parts of the still images are made of a same image or alternatively at least parts are made of same images with parallax. The binocular image display apparatus of the present invention is of the kind known from GB-A-2129994 which comprises: right-eye and left-eye moving image display means for displaying respective right-eye and left-eye parallax moving images of a same moving object scene viewed from respective viewpoints; right-eye and left-eye still image display means for displaying respective right-eye and left-eye still images; and optical means, arranged relative to each of said display means, for directing light from said right-eye moving and still image display means to the right-eye pupil of an observer, and for directing light from said left-eye moving and still image display means to the left-eye moving and still image display means to the left-eye pupil of the observer whereby the observer is enabled to fuse the viewed images, which right-eye moving and still images and left-eye moving and still images are viewed at a convergence angle; relative to the perpendicular bisector plane of a base line joining the left- and right-eye pupils. In GB-A-2129994 a colour slide is used as a stationary background image for right-eye and left-eye image display. The binocular image display apparatus of the present invention is characterised by: actuation means, co-operative with the optical means, to set the convergence angle; control means, responsive to input control information, co-operative with the actuation means, to control the setting of the convergence angle, whereby the observer shall view the parallax moving images as fully or partially overlapped virtual images such that corresponding points of the right-eye and left-eye parallax moving images displaced by parallax shall be viewed as coincident; and selection means, co-operative with the control means, for selecting suitable right-eye and left-eye still images for display by the right-eye and left-eye still image display means which suitable still images are viewable either fully or partially overlapped correspondingly, the ratio of overlap thereof, depending on the setting of the convergence angle. It is acknowledged that European Patent Application EP-A-0617549 (mentioned with reference to Art. 54(3) EPC) discloses a binocular image display apparatus for HMD using changing means which can change a convergence angle of displayed images for the left and right eyes whereby the apparatus can display not only a stereoscopic image but also a two-dimensional panorama image in a variable aspect ratio and can also display a mixed image of a stereoscopic image and a two-dimensional image, and further using combiner elements for superimposing external view images on such images whereby the observer can observe both images at a time. In the conventional binocular image display apparatus, for example, supposing an angle of view of the optical systems is 30° and the position of the virtual images of the displayed images is located 1 m ahead of the observer, the LCDs a little less than an inch (1 inch = 2.54 cm (diagonal)) are perceived as displays of about 30 inches 1 m ahead on calculation. However, though the angle of view was actually 30°, there was no information giving the sense of distance, "1 m ahead". Because of this, the observer was not always able to perceive them as displays of 30 inches 1 m ahead, but tended to perceive that there were compact displays in front of the eyes, raising a problem of it being hard to realise appreciation of presence on a large screen, with a feeling of being natural, but without fatigue. In addition, the disclosed binocular image display apparatus is so arranged that, for example, the convergence angle of left and right displayed images was changed to shift the virtual images in the horizontal direction whereby an overlapping region of the left and right images is changed so as to change the aspect ratio of a displayed image for the both eyes. In this case, for fusion of the left and right images depending upon the overlapping region, common parts of the displayed images is finally left to human processing by the brain after being observed by the retina. This causes a problem that it is difficult for the observer to naturally follow a change in the aspect ratio upon switching of scenes, resulting in the observer feeling tired and thus making long-period observation difficult. Some specific examples of the image display apparatus of the present invention will be described by way of example only in the following description of the preferred embodiments, made with reference to the accompanying drawings wherein: Fig. 1 is a schematic drawing of major part of embodiment 1 in which the present invention is applied to a head mounted display (HMD); Fig. 2 is an explanatory drawing to illustrate a displayed image viewed using the apparatus of fig. 1; Fig. 3 is a schematic drawing of major part of embodiment 2 in which the present invention is applied to another head mounted display (HMD) of modified construction; Fig. 4 is an explanatory drawing to illustrate a displayed image viewed using the apparatus of Fig. 3; Fig. 5 is a schematic drawing of major part of embodiment 3 in which the present invention is applied to yet another head mounted display (HMD) of further modified construction; and Fig. 6 is an explanatory drawing to illustrate a displayed image viewed using the apparatus of Fig. 5. Fig. 1 is a schematic drawing to show the major part of embodiment 1 where the present invention is applied to a head mounted display (hereinafter referred to as "HMD"). In Fig. 1, reference symbols 1L, 1R designate the left eye and the right eye, respectively, of an observer. In the following description, letters L, R mean elements for the left eye and for the right eye, respectively. Further, D is a distance between the pupils of the both eyes (i.e., the base length). Also, Q is a middle point of the base length D. Further, 3L, 3R each are liquid crystal display means (hereinafter also referred to as "LCD"), each of which has a first or second liquid crystal display portion (hereinafter referred to as "moving image LCD") 4L, 4R as moving image display means illuminated by a backlight 7L, 7R as a first or second illuminating portion, and a third or fourth liquid crystal display portion (hereinafter referred to as "reference LCD") 5L, 5R as still image display means illuminated by a backlight 8L, 8R as a third or fourth illuminating portion. Each of the moving image LCDs 4L, 4R and the reference LCDs 5L, 5R is made of a transmission-type liquid crystal panel, which is composed of a colour filter and two polarizing plates set on the two surfaces thereof in a crossed Nicols arrangement. The moving image LCDs 4L, 4R and the reference LCDs 5L, 5R each are arranged in close fit or incorporated with the backlight 7L, 7R and the backlight 8L, 8R, respectively, but Fig. 1 shows them separated from each other for convenience sake. The number of pixels in each of the moving image LCDs 4L, 4R is greater than that in each of the reference LCDs 5L, 5R. Each of 2L and 2R is a lens system as optical means, by which light from the liquid crystal display portions 3L, 3R is guided to the observer's pupil whereby a displayed image on the liquid crystal display portions 3L, 3R is displayed as a virtual image ahead of the observer. Each of 11L, 11R is an LCD drive circuit, which drives each of the moving image LCDs 4L, 4R and the reference LCDs 5L, 5R. Also, each of 12L, 12R is a backlight drive circuit, which drives each backlight 7L, 7R and each backlight 8L, 8R. Numeral 13 denotes a commander or remote controller. Each 10L, 10R is an image processing circuit, which supplies image information to the LCD drive circuits 11L, 11R. Numeral 9 denotes a controller for drive-controlling various circuits. Letter I denotes a signal input terminal. Numeral 14 designates a virtual image plane of the liquid crystal display portions 3L, 3R defined by the lens system 2L, 2R. Letter P denotes a middle point of the virtual image plane 14. Each of 15L, 15R is a virtual image of an image displayed on the liquid crystal display portions 3L, 3R. ML, MR represents a middle point of the virtual images 15L, 15R, respectively. Each of 16L, 16R is an optical axis for the left eye and for the right eye, respectively. Numeral 17 represents a perpendicular bisector plane of the base length D, which intersects at point Q with the base length and at point P with the virtual image plane. L, R is an angle which the optical axis 16L, 16R, respectively, makes with the perpendicular bisector 17 (hereinafter referred to as "convergence angle"). In the present embodiment, image information and accompanying control information is supplied through the signal input terminal I from an external binocular camera, a memory such as a tape or a disk, or a communication line, etc. and is then put into the image processing circuits 10L, 10R and controller 9, respectively. With the control information put into the controller 9 and identification information on either left or right image attached to the header of the picture information, the image processing circuit 10L, 10R separates the left or right image signal from the other, subjects it to necessary image processing, and thereafter makes the moving image LCD 4L, 4R display a moving image through the LCD drive circuit 11L, 11R. The present embodiment shows an example where information of a stereoscopic moving image is displayed. Namely, the controller 9 determines from the input control signal if the information is of a stereoscopic moving image. Then, determining the convergence angles L, R for HMD, it drives an actuator (not shown) to set the optical axis 16L, 16R of HMD to the determined convergence angle L, R before display of moving image. Further, receiving a control signal and an input signal from the commander 13, the controller 9 selects an image to be displayed on the reference LCD 5L, 5R out of candidates of suitable reference still images for stereoscopic images prepared earlier, and displays it thereon through the LCD drive circuit 11L, 11R. The reference still image 5L, 5R to be selected at this point is supplied from a ROM inside the commander 13 or a reloadable memory such as an IC card etc. The display of reference still image 5L, 5R is given before display of moving image, but the apparatus is so arranged that the observer can again select another still image depending upon the contents of moving image through the commander 13. The backlights 7L, 7R, 8L, 8R start illumination at a matched timing with display start of moving image LCDs 4L, 4R and reference LCDs 5L, 5R. The luminance of backlight 8L, 8R may be adjusted depending upon the contents of reference LCDs 5L, 5R, or the luminance may be adjusted to effect fade-in or fade-out. Also, the apparatus may be so arranged that the adjustment of luminance or an on/off control of illumination is made through the commander 13 under the observer's control. Fig. 2 is an explanatory drawing of virtual image observed using the HMD of Fig. 1. In Fig. 2, 2OL, 2OR correspond to the virtual images 15L, 15R in fig. 1. Further, 21L, 21R correspond to the virtual images of the displayed images on the reference LCDs 5L, 5R; and 22L, 22R to the virtual images of the displayed images on the moving image LCDs 4L, 4R. 23L, 23R is an exit pupil of lens system 2L, 2R, by which the virtual images 21L, 21R are eclipsed in the outside region of the pupils where the image is out of observer's field of view. Point P is the centre of the virtual image plane 14 while ML, MR are the centres of the left and right virtual images. The points P, ML, MR are coincident with each other. The virtual images 22L, 22R of the moving image LCDs and the still images 21L, 21R of the reference LCDs are parallax images with convergence angles L, R, so that corresponding points in same images with parallax are coincidentally superimposed on each other on the entire image plane. The still image 21L, 21R of the reference LCD is made of an image preliminarily photographed so as to match with a 30-inch screen in an aspect ratio of 3:2, which is the screen size of the virtual image 22L, 22R of the moving image LCD 1 m ahead. This makes the observer wearing the HMD perceive that there is actually a display of 30 inches 1 m ahead of the observer. Further, even with changes of various scenes in the virtual images 22L, 22R of the moving image LCDs, the fusion of parallax images with convergence angles L, R is constantly continued using information of still images 21L, 21R, regardless of the contents of the virtual images 22L, 22R. This realizes display of a more natural stereoscopic image, so that the observer can appreciate the display for a long time period with little fatigue. Although the stereoscopic image is more natural and effective for the still images 21L, 21R on the reference LCDs in the present embodiment, the effect of the present invention can also be achieved similarly as described above by such an arrangement that two-dimensional still images, i.e., same images without parallax, are displayed on the left and right reference LCDs 5L, 5R in order to save memory capacity. Fig. 3 is a schematic drawing to show the major part of embodiment 2 where the present invention is applied to a seethrough-type HMD. The present embodiment is different from embodiment 1 of Fig. 1 in that the HMD is of a seethrough type having a function to display images from LCDs 3L, 3R and an image such as an external view in a spatially superimposed manner using aspherical combiners 6L, 6R so as to permit the observer to simultaneously observe the both images, and is constructed in the same structure except therefor. In Fig. 3, the same elements as those shown in Fig. 1 are denoted by the same reference numerals. The present embodiment is so arranged that images from LCDs 3L, 3R are once focused at secondary image positions 18L, 18R by lens systems 2aL, 2aR and the images at the secondary image positions 18L, 18R are guided to the pupils of the two eyes 1L, 1R by the combiners 6L, 6R, whereby virtual images 15L, 15R of the images on the LCDs 3L, 3R are formed in the vicinity of the virtual image plane 14. A field stop as detailed later is located at each secondary image position 18L, 18R. 19L, 19R is a liquid crystal shutter, which is a shutter for performing an on/off control of input of the seethrough external field image therethrough into the pupil 1L, 1R. The present embodiment shows an example where the seethrough-type HMD is arranged to operate in a mixed image mode wherein 50% of virtual images 15L, 15R for the left and right eyes are superimposed on each other. The overlapping region is viewable as a stereoscopic image portion, while the non-overlapping regions are viewable as two-dimensional image portions of the viewed image. The centre ML of the virtual image 15L for the left eye is shifted to the left from the middle point P, so that it is located at a position nearly coincident with an image of the left edge of the virtual image 15R for the right eye. This is also the case for the virtual image 15R for the right eye. Thus, the convergence angles L, R are narrower than those in the stereoscopic image mode of embodiment 1 of Fig. 1. In the present embodiment, based on control information supplied through the signal input terminal I, the controller 9 drives the actuator (not shown) to set the convergence angles L, R for displaying the predetermined mixed image of two-dimensional images and a stereoscopic image. Receiving the control information and an input signal from the commander 13, the controller 9 forms 30-inch displays in an aspect ratio (length:height) of 3:2 at 1 m ahead in correspondence with the mixed image of two-dimensional images and a stereoscopic image so as to overlap 50% with each other. Namely, the controller 9 selects reference still images matching with a display in an aspect ratio of 9:4 at present 1 m ahead and displays them on the reference LCDs 8L, 8R. These two functions achieve fusion of the mixed image of two-dimensional images and a stereoscopic image overlapping 50 %. In this connection, the apparatus is so arranged that a signal from the controller 9 is given through the backlight drive circuit 12L, 12R to close the liquid crystal shutter 19L, 19R so as to interrupt the external view and that, turning off the backlight 7L, 7R for the moving image LCD 4L, 4R or making the moving image LCD 4L, 4R display uniform white or black, illumination is effected by the backlight 8L, 8R for reference LCD 5L, 5R, which facilitates the fusion of the reference still images. After completion of the above setting, the mixed image of the two two-dimensional images and the stereoscopic image are displayed on the moving image LCDs 4L, 4R, whereby the observer can constantly appreciate the mixed moving image of the two two-dimensional images and the stereoscopic image in a more natural state without being affected by switching of scenes in the image and without fatigue. When the observer desires to watch the seethrough image of the external view, a necessary operation is just opening the liquid crystal shutters 19L, 19R. In that case, the seethrough external view can be recognized better by turning off the backlights 8L, 8R and reference LCDs 5L, 5R to stop the display of the reference still images. However, it causes no problem where the observer wants to watch mainly the seethrough external view, but the size of the moving image displayed is influenced by the external field. Namely, the size of the moving image is perceived smaller when the observer looks near the observer's hand in the seethrough condition; conversely, the size is perceived larger when the observer gazes into the distance in the seethrough condition. If a weighting is placed on observation of the image information displayed on the moving image LCDs 4L, 4R rather than the seethrough external view, the reference LCDs 5L, 5R are driven to display the still images and the backlights 8L, 8R are turned on to effect illumination in order to suppress the change of display size due to the seethrough external view. The liquid crystal shutters 19 can be closed as and when necessary. Fig. 4 is an explanatory drawing to illustrate image information observed with the seethrough-type HMD of the present embodiment. In Fig. 4, each 24L, 24R is a field frame placed at each secondary image position 18L, 18R. Each 25L, 25R is the displayed image on the moving image LCDs 4L, 4R; each 26L, 26R the virtual image of the displayed image on the reference LCDs 5L, 5R, and the points P, ML, MR are those described with Fig. 3. The exit pupil is originally circular as shown in Fig. 2, but the present embodiment uses the field frames 24L, 24R provided at the secondary image positions 18L, 18R to shape the field to match the shape of the displayed image, which makes the displayed image more natural and easier to watch. Here, the effect of the present invention can also be attained similarly as described previously by using two-dimensional images without parallax as the reference still images 26L, 26R similarly as in the case of the image shown in Fig. 2. Fig. 5 is a schematic drawing to show the major part of embodiment 3 where the present invention is applied to another HMD. The present embodiment is different from the embodiment 1 of Fig. 1 in that the combiners 6cL, 6cR are each made of a plane half mirror and are arranged to display virtual images 15L, 15R of displayed images on moving image LCDs 4L, 4R and a displayed image (left and right eye images) on a single reference LCD 5a in a spatially combined manner whereby the observer can simultaneously observe both images,and is constructed n the same structure except therefor. In Fig. 5, the same elements as those shown in Fig. 1 are denoted by the same reference numerals. In Fig. 5, each 27L, 27R is a drive circuit for moving image LCDs 4L, 4R and a drive circuit for backlight 7L, 7R thereof. Numeral 28 designates a drive circuit of reference LCD 5a and backlight 8a thereof. The reference LCD 5a and backlight 8a cover a wider angle of view than the angle of view of the moving images displayed by the HMD in the present embodiment. Particularly, the horizontal angle of view covers a wide angle of view twice greater than the horizontal angle of view of the left and right moving images. Numeral 29 is a light shield plate, which is vertically set at the centre Pa of the reference LCD 5a in order to separate out images for the left eye and right eye respectively, that is, in order to prevent the left eye from observing the image for the right eye, and vice versa. The present embodiment is arranged here to operate in a panoramic view mode wherein the images on the moving image LCDs 4L, 4R and the image on the reference LCD 5a are combined to be observed, the images for the left and right eyes are juxtaposed adjacent to each other in a two-dimensional manner so as to allow observation of a panorama image. Namely, the virtual images ML, MR for the left and right eyes abut each other at point P. The optical axes 16L, 16R of the optical systems are set to have the convergence angles L, R matching with the two-dimensional panorama image, similarly as in embodiment 2, and an appropriate reference still image 5a for the two-dimensional panorama is selected and displayed. When the two-dimensional panorama image is displayed, the convergence angles L, R of the optical axes 16L, 16R of HMD are negative, but the convergence angles of the observer's visual axes are not negative. The still image displayed on the reference LCD 5a indicates the black level in the region where the virtual images of the moving images are put. Since the reference LCD 5a of the present embodiment is a single panel, the image is also a two-dimensional image even in display of moving images having a stereoscopic image region as shown in Fig. 2 or Fig. 4 with a change of convergence angles, but the perceptive effect of the panel size is not degraded thereby at all. Also, the apparatus is originally so arranged that with change of the convergence angles L, R of the optical axes 16L, 16R by the actuator (not shown), the reference still image LCD 5a split corresponding to the left and right eyes is similarly changed. achieves an effect to promote the fusional function. However, because the reference LCD 5a of the present embodiment is a single panel, a single two-dimensional image is basically displayed unless time-division display is employed, which would lower the fusional effect. Then, upon change of the convergence angles, the displayed image on the reference LCD 5a is split into portions in the horizontal direction and the portions are moved matching with the movement of the virtual images through the drive circuit 28 by a movement signal from the controller 9. This achieves the same effect. Originally, the reference still image is split similarly as the left and right virtual images are, which is effective to maintain the constancy of image fusion. To the contrary, the present embodiment employs a single panel, but obtains the same effect by displaying the spatially separate left and right images left and right of the light shield plate 29 with the centre at the intersections MaL, MaR on the optical axes 16L, 16R and the LCD 5a, as described above. The present embodiment showed an example where the position along the optical axis, of the real image 5a was different from that of the virtual images 15L, 15R. When the observer's eyes are focused on the virtual images, a decrease in the effect due to defocus is normally small because the reference image 5a is assistant. Fig. 6 is an explanatory drawing to illustrate virtual images 31L, 31R and a reference real image 30 observed in the present embodiment. The reference images in each of the three embodiments 1, 2, 3 as described above have patterns that can be fused easily, especially in the overlapping portion. Particularly, the patterns in the fused portions influence the effect in the case of Fig. 4 or Fig. 6. A fusion assist pattern S for that purpose is provided in the reference still image in each of the embodiments 1, 2,3 of Fig. 2, Fig. 4, and Fig. 6. A preferable pattern employed is one by which horizontal positional deviation can be clearly perceived. It is acknowledged that the use of fusion assist patterns is known. For example, US-A-5002363 discloses a stereoscopic image viewer in which a stereoscopic image sheet has discernible pattern markings, e.g. circles, provided in the lower side margin of the right-eye and left-eye image portions thereof. Although a pattern of a circle or a cross may be employed, a pattern not so sensitive to vertical positional deviation is preferable because it can decrease fatigue due to fusion. However, considering that the image is horizontally long and that the vertical positional deviation is actually rare because of the mechanism, preferable patterns are simple patterns having asymmetry in the horizontal direction, as shown in the above embodiments. Further, the above embodiments 1, 2, 3 employed LCD panels for displaying reference still images, but a transmission-type still image such as a slide may be used instead of the or each LCD panel to attain the same function and effect of the present invention. Besides, to handle a change of the aspect ratio in the present embodiment, the still image may be exchanged for one matching with the changed aspect ratio. Where the virtual images are observed with the reference still images placed at the same position as the moving image LCDs 7L, 7R as in the embodiment 1 or 2 of Fig. 1 or Fig. 3, a possible arrangement is such that images which are transparent in the overlapping region with the moving image LCDs 7L, 7R in the reference still images are prepared, the left and right images are transferred by the silver salt technology or by the printing technology, etc. onto a film or plastic thin plate, and a mechanism is provided for inserting left and right still image panels packaged in a field frame or the like in periphery, before the moving image LCDs 7L, 7R. On the other hand, where they are placed at the secondary image positions 18L, 18R as in embodiment 2 of Fig. 3, the same effect can be attained by setting the still image panels provided with the additional function of the field frames 24L, 24R at the secondary image positions 18L, 18R. In the case of embodiment 3 of Fig. 5, the same effect is achieved by inserting a single still image panel at the position of LCD 5a.

Claims: A binocular image display apparatus comprising: right-eye and left-eye moving image display means (4R,4L) for displaying respective right-eye and left-eye parallax moving images (22R,22L; 25R,25L) of a same moving object scene viewed from respective viewpoints; right-eye and left-eye still image display means (5R,5L) for displaying respective right-eye and left-eye still images (21R,21L; 26R,26L); and optical means (2R,2L; 2aR,bR,2aL,6L), arranged relative to each of said display means, for directing light from said right-eye moving and still image display means to the right-eye pupil (1R) of an observer, and for directing light from said left-eye moving and still image display means to the left-eye pupil (1L) of the observer whereby the observer is enabled to fuse the viewed images, which right-eye moving and still images and left-eye moving and still images are viewed at a convergence angle ( R , L ) relative to the perpendicular bisector plane (17) of a base line joining the left- and right-eye pupils, characterised by: actuation means (-), co-operative with said optical means, to set said convergence angle; control means (9), responsive to input control information, co-operative with said actuation means, to control the setting of said convergence angle, whereby the observer shall view the parallax moving images as fully or partially overlapped virtual images such that corresponding points of the right-eye and left-eye parallax moving images displaced by parallax shall be viewed as coincident; and selection means (13), co-operative with said control means, for selecting suitable right-eye and left-eye still images for display by said right-eye and left-eye still image display means which suitable still images are viewable either fully or partially overlapped correspondingly, the ratio of overlap thereof, depending on the setting of said convergence angle. Apparatus according to claim 1, which apparatus also is operable in a panorama view mode, wherein said right-eye and left-eye moving image display means also are for displaying respective right-eye and left-eye apportioned panoramic moving images of a moving object scene; said control means is adapted to control the setting of said convergence angle whereby the observer shall view the right-eye and left-eye apportioned panoramic moving images in abutment to view a resultant panoramic image; and said selection means is adapted for selecting suitable right-eye and left-eye apportioned panoramic still images viewable in abutment. Apparatus according to either preceding claim wherein said display means and said optical means are arranged for forming virtual images of said moving images and still images in a common plane (14). Apparatus according to claim 3 wherein: said right-eye moving and still image display means (4R,5R) are arranged with their display planes co-planar; and said left-eye moving and still image display means (4L,5L) are arranged with their display planes co-planar. Apparatus according to claim 4 wherein said optical means (2aR,6R,2aL,6L) includes optical combiners (6R,6L) interposed in the light path of said display means, arranged to enable see-through viewing of an object scene in front of the observer, superimposed with the viewed moving and still images. Apparatus according to claim 5, including shutter means (19R,19L) arranged in front of said optical combiners for selectively observing the object scene in front of the observer. Apparatus according to either of claims 1 or 2 wherein said right-eye and left-eye still image display means are arranged in the field of view of said optical means with their respective display planes located non-coplanar with the respective display planes of said right-eye and left-eye moving image display means. Apparatus according to claim 7 wherein said right-eye and left-eye still image display means comprise a single display means (5a) having a light shield plate (29) arranged to prevent viewing of the left-eye still image by the right-eye of the observer and to prevent viewing of the right-eye still image by the left-eye of the observer. Apparatus according to claim 8 wherein said single display means is a liquid crystal display panel. Apparatus according to any preceding claim including optical transparency storage means for storing optical transparencies on which, respectively, are recorded right-eye and left-eye still images, which optical transparencies are selectable from said storage means for display of the right-eye and left-eye still images by said right-eye and left-eye still image display means. Apparatus according to claim 10 including optical transparencies stored in said storage means. Apparatus according to any preceding claim 1 to 8 including still image data storage means for storing image data of right-eye and left-eye still images selectable by said selection means for use by said right-eye and left-eye still image display means. Apparatus according to claim 12 including still image data stored in said storage means. Apparatus according to either of claims 11 and 13 wherein paired right-eye and left-eye still images are parallax still images of a still object-scene viewed from respective viewpoints. Apparatus according to either of claims 11 and 12 wherein paired right-eye and left-eye still images each include a respective reference pattern (S), which patterns are asymmetric in the horizontal direction and are superimposable to assist in the image fusion performed by the observer. A method of operating the image display apparatus of claim 1 including steps of: inputting image information and control information for displaying the right-eye and left-eye moving images; setting the convergence angle for viewing the right-eye and left-eye moving images in accordance with the input control information; selecting the right-eye and left-eye still images in accordance with the convergence angle setting; displaying, as virtual images, the selected right-eye and left-eye still images; and displaying simultaneously, as virtual images, the right-eye and left-eye moving images surrounded by the virtual images of the right-eye and left-eye still images. A method according to claim 16 wherein the convergence angle setting is maintained for a given still image selection while a sequence of moving images of different moving object scenes are displayed.

Inventors: HOSHI HIROAKI, HOSHI, HIROAKI
Applicants: CANON KK, CANON KABUSHIKI KAISHA
Application year: 1994
Main classification: G02B27
IPC codes: G02B27, H04N13